Cement foe Leathee.—The Coadimakers' Journal says, of the many substances lately brought very conspicuously to notice for fastening pieces of leather together, and in mending harness, joining machinery-belting, and making shoes, one of the best is made by mixing ten parts of sulphide of carbon with one of oil of turpentine, and then adding enough gutta-percha to make a tough thickly flowing liquid. One essential pre-requisite to a thorough union of the parts consists in freedom of the surfaces to be joined from grease. This may be accomplished by laying a cloth upon them and applying a hot iron for a time. The cement is then applied to both pieces, the surfaces brought in contact, and pressure applied until the joint is dry. Matueity of Wines.—Dr. Dupre, lecturer on chemistry at Westminster hospital, states in a paper on wine, recently published, that pure natural wine may be considered to have arrived at maturity at the end of from five tefwelve years. In that time, he remarks, the slow chemical changes which bottled wine undergoes will have produced their best effect; and after that, " the wine no longer improves by keeping, except to the taste of a few would-be connoisseurs." But there are exceptions to this rule—namely, wines unusually rich in quality, and those which are " fortified " by alcohol. Such wines continue to improve up to the end of fifteen years. The supposed cavities in diamonds, described by Brewster, are shown to be in reality inclosed crystals; and the conclu sion arrived at, from the consideration of the whole structure of the diamond, is not opposed to its having been formed at a high temperature. The crystals inclosed in diamonds are frequently seen to be surrounded by a series of fine radiating cracks, which are proved to have been the result of the contraction suffered by the diamond in solidifying over the inclosed crystal. This explanation has been artificially verified by examining crystals formed in fused globules of borax g ass, cooled slowly, when the same phenomena are seen. INTELLIGENCE OP Ants.—Each ant in an ant-hill knows its companions. Mr. Darwin several times carried ants from one Jtlill to another, inhabited apparently by tens of thousands of ants; but the strangers were invariably detected and killed. Thinking that there might be a family odor by which they were recognized, he put some ants from a very large nest into a bottle strongly perfumed with asatcetida, and restored them after twenty-four hours. At first they were threatened by their companions, but soon recognized, and allowed to pass. Vaenishing Peints.—The following method of varnishing photographic prints is recommended by a correspondent: A piece of plate glass is heated, and, while yet warm a little wax is rubbed overit by means of a piece of cotton wool; water is then poured over the plate, and the moistened picture laid thereon and pressed closely down by means of a piece of filtering paper. When dry the picture is removed and will be found to possess a surface of the greatest brilliancy, which is not injured by the process of mounting. A Feench Journal publishes the following cure for hydrophobia. When a person has been bitten by a mad dog let him take seven (?) vapor baths, called Russian baths, ranging in temperature from fifty-seven to sixty-three degrees. This is the preservative treatment. When the disease shows itself let the bath be rapidly brought up to fifty-seven degrees and then slowly increased to sixty-three degrees. In the latter case one bath suffices, but the patient must carefully keep his room until he is thoroughly cured. Cocoanut Fibee.—At a recent meeting of the Polytechnic Society of Liepsic, one of the members asserted that belting for machinery could be made of cocoanut fiber, possessing for this purpose many advantages in economy, durability, and applicability, over leather, rubber, and other substances most commonly used. How the proposed belting is to be made we have not learned. Chief Engineee James W. King has been nominated to be Chief of the Bureau of Steam Engineering. President Grant states at the bottom of his order " in place of Isherwood whom I desire removed." It is very evident that the President means reform and we are glad to see him striking at the root of the matter.